body{
    background-image: url("../img/1.jpg");
    background-position:center 0;
    background-repeat: no-repeat;
    background-attachment: fixed;
    background-size: cover;
    -webkit-background-size: cover;
    -o-background-size: cover;
    -moz-background-size: cover;
    -ms-background-size: cover;
}

.input_show{
    margin-top: 35px;
    max-width: 280px;
    height: 35px;
}

.btn_num{
    margin: 1px 1px 1px 1px;
    width: 60px;
}

.btn_clear{
    margin-left: 40px;
    margin-right: 20px;
}

.extendContent{
    height: 300px;
}